We've seen it in Cruel Intentions, we've seen it in 10 Things I Hate About You, hell, we've seen it in SPY KIDS.
The idea that someone is paid or challenged to get close to a girl and end up falling for them.
Brother and sister meet a goodie two-shoes girl who they want to 'spoil.' The sister dares the brother to do whatever it takes to woo the girl and make her behave "badly."
Spoiler, they fall in love. DUH.
The ending is so ridiculous I can't ruin it for you, but the whole movie is so incredibly over the top I seriously suggest it to everyone (probably over the age of 13 lol)
10 Things I Hate About You
Girl can't go to the school dance because her dad's rule is that her older sister needs to go too. Both of them can go, or none of them can go. SO she enlists the help of a boy who enlists ANOTHER boy (read: Heath Ledger) to get his sister to go to the dance.